As you might have noticed I recently uploaded my official contest video to Youtube. If you haven't seen it, it's embedded a bit further below. 

If you've been following along you might notice that the barrel jack connector has mysteriously disappeared and has seemingly been replaced by a USB-connector. The explanation here is that I did manage to squeeze in the 74hc74 flip flop onto the board to have the PS/2 keyboard connecting straight to the board without a daughterboard - a nice trade for a barrel jack. In return two pairs of 5V+GND 0.1" headers have been added - J1 and J8. 
At the same time I also managed to squeeze in another 74HC00 NAND IC, which let me fix the control register decoding - it now only listens on write cycles and has been moved to $7000, which means more RAM freely accessible. This has also been fixed in the project details. 

For this build I also managed to make the address space from $4000 to $5FFF jumper selectable - which means it's easier to switch between using it as RAM or IO space, shorting either R26 for RAM or R27 for making it floating address space. 

The character ROM also got another address line enabled which means each "bank" now has 256 characters instead of 128 - that should make it easier to fit some PETSCII pixel art characters in there without switching banks. 

Lastly I've added a bunch of 0402 jumper pads which understandably scared a newcomer away from ordering a board - for now they are intended as a test/debugging way of skipping the 74HC245's as I suspect they might not be needed when using a 'C02 since it also has the BE pin which should do the same and float the address bus. 

I did manage to need one bodge since I also removed the unnecessary phi2 buffering but forgot to connect Ø2B and PHI0 (Aka 2MHz) - super easy fix and already fixed in the gerbers. 

I regret moving some of the pinheader jumpers to 0402 pads, since 0402 pads are surprisingly resistant to being solder bridged - I will absolutely find a better footprint for the solder bridge jumpers before I order more PCB's. 

From the Youtube comments I also learned that 0603 capacitors might also be on the small side for most interested people - so I might up that to 0805's as well. It really is meant to be solderable by a hobbyist with a relatively huge soldering iron - though power supply might have to be via pin header now that the barrel jack is out of the picture.

So, is this a new "revision"? Meh - I've decided it's merely a new "build" as most of these changes were always intended to be part of R1 and most of the routing and general idea remains the same. So say hello to the ABN6502 SBC R1 B2 - now with a USB port for PS/2 keyboards. 

Thanks for the support to everyone so far!